阅读说明：本技术 用于在能围绕转动轴线转动的底座上制造至少一个固体层的方法 (Method for producing at least one solid layer on a base that can be rotated about an axis of rotation ) 是由 H·玛西亚 于 2020-04-17 设计创作，主要内容包括：在用于根据预定的几何数据在能围绕转动轴线(2)转动的底座(1)上制造至少一个固体层的方法中,提供发射体装置(11),其具有多个构造成材料输出喷嘴的发射体,发射体以发射体列和发射体行布置。在转动轴线(2)的周向方向上彼此相邻的发射体列分别在发射体列的延伸方向上彼此错开,使得发射体以不同的距转动轴线(2)径向距离DA(i)布置,其中DA(i)＞DA(i+1),几何数据配设有打印点,打印点在具有多个并排延伸的排的矩阵中彼此错开,使得PA(j)＞PA(j+1),PA(j)是所涉及的排的第j个打印点P-(j)到转动轴线(2)的径向距离。对于材料应当被输出到底座(2)上的打印点P-(k),分别从发射体装置的配设给所涉及的打印点P-(k)的发射体D-(k)中输出至少一个材料部分。材料部分的输出在多个打印周期中进行,在各打印周期中为了输出材料分别在配设给所涉及的打印周期的触发部位处触发一次发射体装置并且底座(1)以及发射体装置分别逐个打印周期地彼此错开一个相对于转动轴线(2)的角度距离。一排的所有打印点的打印在多个打印周期中进行,打印周期数量大于发射体列数量。对于每个待打印的打印点分别这样选择打印周期,使得当底座(1)相对于发射体装置定位在触发部位处时,打印周期的触发部位的转动位置与待打印的打印点相对于转动轴线所布置的转动位置之间的角度差在数值上不大于各触发部位之间的角度距离的一半。(At the bottom for rotating around the rotation axis (2) according to the predetermined geometric dataIn a method for producing at least one solid layer on a substrate (1), an emitter arrangement (11) is provided, which has a plurality of emitters configured as material outlet nozzles, the emitters being arranged in emitter columns and emitter rows. Emitter rows adjacent to one another in the circumferential direction of the axis of rotation (2) are offset from one another in the direction of extent of the emitter rows in each case such that the emitters are arranged at different radial distances DA (i) from the axis of rotation (2), DA (i) > DA (i +1), the geometric data being assigned printing points which are offset from one another in a matrix having a plurality of rows extending next to one another such that PA (j) > PA (j +1), PA (j) being the jth printing point P of the row concerned j Radial distance from the axis of rotation (2). For printing points P where material is to be output onto a base (2) k From the associated printing point P of the emitter device k Emitter D of k At least one material portion is output. The output of the material portions is carried out in a plurality of printing cycles, in each of which the emitter device is triggered once in each case at a triggering point assigned to the printing cycle concerned for the output of the material, and the base (1) and the emitter device are offset from one another by an angular distance relative to the axis of rotation (2) in each case one printing cycle after the other. Printing of all the printed dots of a row occurs in a number of print cycles, the number of print cycles being greater than the number of emitter columns. The printing cycle is selected for each print point to be printed in such a way that, when the base (1) is positioned at the triggering point relative to the emitter device, the angular difference between the rotational position of the triggering point of the printing cycle and the rotational position at which the print point to be printed is arranged relative to the rotational axis is not greater in value than half the angular distance between the triggering points.)

1. Method for producing at least one solid layer on a base (1) that can be rotated about an axis of rotation (2) according to predetermined geometric data,

a) in order to output the material portion of the nozzle common material onto the base (1), an emitter arrangement (11, 11A to 11D, 11A 'to 11D') is provided, which has a number N of emitters (12) forming a material output nozzle, which are arranged in a matrix form in emitter rows (13) offset parallel to one another and in emitter rows (14) offset parallel to one another and extending transversely to the emitter rows (13), the emitter rows (13) adjacent to one another in the circumferential direction of the axis of rotation (2) being offset from one another in the direction of extension of the emitter rows (13) in each case, such that the individual emitters (12) of the emitter arrangement (11, 11A to 11D, 11A 'to 11D') are arranged at different radial distances DA (i) from the axis of rotation (2), wherein:

DA(i)＞DA(i+1)

wherein i belongs to [1. (N-1) ],

b) the geometric data is provided with printing points P_M...P_M+NThe printing dots are offset from one another in a matrix having a plurality of rows (20) extending alongside one another, in each of which a number Q of printing dots are arranged, so that:

PA(j)＞PA(j+1)，

wherein j belongs to [ M. (M + N-1) ] and M is more than or equal to 1 and less than or equal to Q-N,

wherein PA (j) is the j-th printing point P of the row (20) concerned_jA radial distance to the axis of rotation (2) and M is an integer,

c) for printing points P where material is to be output onto a base (2)_kFrom the respective associated printing points P of the emitter devices (11, 11A to 11D, 11A 'to 11D')/_kEmitter D of_k(12) Wherein k is an integer between M and M + N-1,

d) the output of the material portions is carried out in a plurality of printing cycles, in each of which a primary emitter device is triggered for the output of the material at a triggering point (A to H) associated with the printing cycle concerned, and the base (1) and the emitter devices (11, 11A to 11D, 11A 'to 11D') are offset from one another by an angular distance (W) relative to the axis of rotation (2) in each printing cycle,

e) all the printing points P to be printed in a row (20)_M...P_M+N-1Is performed in a number of print cycles which is greater than the number of emitter columns (13),

f) the printing cycle is selected for each print point to be printed in such a way that, when the base (1) is positioned at the triggering points (A to H) relative to the emitter device (11, 11A to 11D, 11A 'to 11D'), the angular difference between the rotational position of the triggering points (A to H) of the printing cycle and the rotational position at which the print point to be printed is arranged relative to the rotational axis (2) is not greater in value than half the angular distance (W) between the triggering points (A to H).

2. Method for producing at least one solid layer on a base (1) that can be rotated about an axis of rotation (2) according to predetermined geometric data,

a) providing a container (22) in which at least one material layer made of a liquid, pasty or powdery material (23) is applied to the base (1), wherein, for irradiating the material (23) with radiation from the solidified material (23), an emitter arrangement (11, 11A to 11D, 11A 'to 11D') is provided, which has a number N of radiation emitters (12) spaced apart from one another and facing the material layer, which are arranged in a matrix form in emitter rows (13) offset parallel to one another and in emitter rows (14) offset parallel to one another and extending transversely to the emitter rows (13), wherein the emitter rows (13) adjacent to one another in the circumferential direction of the axis of rotation (2) are offset from one another in the extension direction of the emitter rows (13) in each case such that the arrangement (11, and 11, D, 11A to 11D, 11A 'to 11D') are arranged at different radial distances da (i) from the axis of rotation (2), wherein:

DA(i)＞DA(i+1)

wherein i belongs to [1. (N-1) ],

b) the geometric data being provided with printed dots (P)_M...P_M+N) The printing dots being offset from one another in a matrix having a plurality of rows (20) extending alongside one another,a number Q of printing dots are arranged in each of the rows, respectively, so that:

PA(j)＞PA(j+1)，

wherein j belongs to [ M. (M + N-1) ] and M is more than or equal to 1 and less than or equal to Q-N,

wherein PA (j) is the j-th printing point P of the row (20) concerned_jA radial distance to the axis of rotation (2) and M is an integer,

c) for printing spots P on which there should be a solid layer_kFrom the respective associated printing points P of the emitter devices (11, 11A to 11D, 11A 'to 11D')/_kEmitter D of_k(12) Wherein k is an integer between M and M + N-1, onto a material (23),

d) the irradiation of the material (23) is carried out in a plurality of printing cycles, in each of which the emitter devices (11, 11A to 11D, 11A 'to 11D') are triggered once for irradiation at the triggering points (A to H) assigned to the printing cycle concerned, and the base (1) and the emitter devices (11, 11A to 11D, 11A 'to 11D') are offset from one another by an angular distance (W) relative to the axis of rotation (2) in each printing cycle,

e) all the printing points P to be printed in a row (20)_M...P_M+N-1Is performed in a number of print cycles which is greater than the number of emitter columns (13),

f) the printing cycle is selected for each print point to be printed in such a way that, when the base (1) is positioned at the triggering points (A to H) relative to the emitter device (11, 11A to 11D, 11A 'to 11D'), the angular difference between the rotational position of the triggering points (A to H) of the printing cycle and the rotational position at which the print point to be printed is arranged relative to the rotational axis (2) is not greater in value than half the angular distance (W) between the triggering points (A to H).

3. Method according to claim 1 or 2, characterized in that the matrix is a cartesian matrix and in that the rows (20) in which the printing dots are offset from each other extend parallel to each other.

4. Method according to claim 1 or 2, characterized in that the matrix is a polar matrix and rows (20) in which the printing dots are offset from each other are arranged radially to the axis of rotation, and preferably rows (20) adjacent to each other are offset from each other by the angular distance (W) of the triggering locations (a to H), respectively.

5. Method according to any one of claims 1 to 4, characterized in that, for a number of directly successive trigger positions (A to H) equal to the number of printing cycles, for the trigger positions (A to H) concerned and for each printed point P, respectively_M...P_M+N-1The emitter arrangement (11, 11A to 11D, 11A 'to 11D') is designed for the printing of the printing point, as the printing point P concerned_M...P_M+N-1One printing cycle is set, and each printing point P to be printed is then individually assigned to each row (20) according to the set_M...P_M+N-1The emitter devices (11, 11A to 11D, 11A 'to 11D') are designed for printing the printing points to be printed, a printing cycle is assigned, and the emitter devices (11, 11A to 11D, 11A 'to 11D') are each triggered when a triggering point (a to H) assigned to the printing cycle concerned is reached.

6. The method according to any one of claims 1 to 5,

a) providing a data memory (19) in which the geometric data are stored,

b) providing a ring memory having a number of storage spaces which is at least equal to the number of printing cycles, each storage space comprising a number (N) of storage positions which is equal to the number (N) of emitters (12) of an emitter arrangement (11, 11A to 11D, 11A 'to 11D'), each of the storage positions being associated with one emitter (12) in each case,

c) for a number of directly successive printing cycles equal to the number of printing cycles, one of the storage spaces is respectively assigned to each of these printing cycles,

d) for a first row (20) of printed dots stored in a data memory (19), reading from the data memory (19) a number (N) of printed dots equal to the number (N) of emitters (12) of an emitter arrangement (11, 11A to 11D, 11A 'to 11D'), the emitter arrangement (11, 11A to 11D, 11A 'to 11D') being designed for the printing of these printed dots,

e) for the emitters (12) associated with the first row (20) of printing dots, an activation value is stored in each storage position of the annular memory associated with the emitters (12), said activation value indicating whether the emitter (12) associated with the printing dot concerned should be activated during a printing cycle associated with the storage space concerned,

f) for the other row (20) of printed dots stored in the data memory (19), reading from the data memory (19) a number of printed dots equal to the number (N) of emitters (12) of the emitter arrangement, the emitter arrangement (11, 11A to 11D, 11A 'to 11D') being designed for the printing of these printed dots,

g) for the emitters (12) associated with the further row (20) of printing dots, an activation value is stored in each storage position of the annular memory associated with the emitters (12), said activation value indicating whether the emitter (12) associated with the printing dot concerned should be activated during a printing cycle associated with the storage space concerned,

h) repeating steps f) and g) until a number of print dots equal to the number (N) of emitters has been respectively read from the data memory (19) for a number of rows (20) equal to the number of printing cycles and for activation values corresponding to these print dots have been stored in the annular memory,

i) positioning the base (1) and the emitter arrangement (11, 11A to 11D, 11A 'to 11D') relative to one another at trigger points (A to H) associated with a printing cycle in the storage space of which the activation value is stored last, and actuating the emitter (12) of the emitter arrangement (11, 11A to 11D, 11A 'to 11D') as a function of the activation value stored in the storage space,

j) if at least one further print dot is to be printed,

-periodically interchanging the storage spaces in such a way that a storage space provided with an activation location (a to H) at which the base (1) and the emitter arrangement are finally positioned relative to each other for activating the emitter (12) is a first storage space, and then

-repeating steps f) to j).

7. Method according to one of claims 1 to 6, characterized in that a print buffer is assigned to the emitter arrangements (11, 11A to 11D, 11A 'to 11D'), in which a storage position is provided for each emitter (12) of the emitter arrangements (11, 11A to 11D, 11A 'to 11D'), in each print cycle an activation signal is stored for each emitter (12) in the storage position of the print buffer assigned to the emitter (12) concerned, in dependence on the geometric data, and subsequently in the print cycle the emitter arrangements (11, 11A to 11D, 11A 'to 11D') are triggered in such a way that the respective emitters (12) are actuated as a function of the activation signal stored in the storage position assigned to the emitter.

8. Method according to claim 7, characterized in that for printing a print ring which is arranged concentrically to the axis of rotation (2) and is defined by an inner circular track and an outer circular track, respectively, at least one first and second emitter device (11, 11A to 11D, 11A 'to 11D') are provided, which emitter devices (11, 11A to 11D, 11A 'to 11D') are positioned relative to the axis of rotation (2) in such a way that the arithmetic mean of the inner circular track and the outer circular track of the first emitter device (11, 11A to 11D, 11A 'to 11D') differs from the arithmetic mean of the inner circular track and the outer circular track of the second emitter device (11, 11A to 11D, 11A 'to 11D'), and the first emitter device (11, 11A to 11D, 11A 'to 11D') is assigned a different second emitter device (11, 11A to 11D, 11A 'to 11D'), 11A to 11D, 11A 'to 11D').

9. The method according to any one of claims 1 to 8, characterized in that the emitter columns (13) of the emitter arrangements (11, 11A to 11D, 11A 'to 11D') are arranged symmetrically with respect to a radial plane formed by the axis of rotation (2) and the normal to the axis of rotation (2) such that the emitter columns (13) extend parallel to the radial plane.

10. Method according to any one of claims 1 to 9, characterized in that at least two emitter arrangements (11, 11A to 11D, 11A 'to 11D') are provided, which are offset from one another by a rotational angle relative to the rotational axis (2), and the emitters (12) of the individual emitter arrangements (11, 11A to 11D, 11A 'to 11D') are each controlled according to at least one of claims 1 to 8 for applying material portions.

11. The method according to one of claims 1 to 10, characterized in that the emitters (12) adjacent to one another within an emitter column (13) are offset from one another by a constant first grid distance, in that the emitter columns (13) adjacent to one another are offset from one another by a constant second grid distance, in each case, and in that the deviation of the first grid distance from the product of the number of emitter columns (13) and the second grid distance is less than 20%, in particular less than 10%, and in particular coincides with this product.

12. Method according to one of claims 1 to 11, characterized in that for producing the three-dimensionally profiled object (17A, 17B, 17C, 17D) a plurality of material layers of nozzle-generic material are applied one above the other, wherein the distance between the emitter device (11, 11A to 11D, 11A 'to 11D') and the base (1) is increased in each case layer by the thickness of the last applied material layer and each material layer is cured separately after its application and then another material layer is applied to it.

13. Method according to one of claims 2 to 11, characterized in that for producing the three-dimensional shaped object (17A, 17B, 17C, 17D) a plurality of material layers of a liquid, pasty or powdery material are cured one on top of the other by irradiation with an emitter device (11, 11A, 11B, 11C, 11D).

Technical Field

The invention relates to a method for producing at least one solid layer on a base that can be rotated about an axis of rotation according to predetermined geometric data.

Background

In the method known from US2004/0265413a1, the geometric data stored in the memory in the form of printed dots of a rectangular coordinate system are converted into polar coordinates by means of a coordinate transformation device. In the method, a 3D printer is provided, which has two emitter arrangements, each having a plurality of emitters spaced apart from one another and designed as nozzles for discharging a material portion of the liquid material onto a base. The base is disk-shaped and can be positioned in a rotary manner about a rotary axis relative to the projectile device by means of a drive device. A rotational position signal for the relative position between the emitter arrangement and the base is generated by means of an encoder.

Furthermore, the base may be positioned in a vertical direction relative to the nozzle arrangement. It is thereby possible to lower the base during the printing process by the thickness of the most recently applied material layer for each revolution in order to apply a further material layer on this material layer and thus to produce the molded object layer by layer.

Each emitter device has a plurality of commercially available print heads which are incrementally movable radially relative to the axis of rotation on a print head support arranged on a sliding guide. Thus, irregularities in printing (which may be caused by an inoperative print head, a stoppage or a wrongly positioned emitter) should be corrected by varying the position of the emitter arrangement layer by layer. The errors caused by emitter shutdowns are therefore arranged at different locations in each printed layer and averaged. Furthermore, the emitter device may be arranged by means of the print head support between a printing position in which the emitter is arranged above the base, a diagnostic position in which the emitter is positioned on the diagnostic device located beside the base, and a maintenance position in which the emitter is positioned beside the base and beside the maintenance position. The projectile may be cleaned or replaced in a service position.

There is no detailed disclosure in this publication of how to accurately arrange the emitters of the emitter arrangement and how to manipulate the emitters during printing.

Furthermore, from practice, 3D printers are known which have a carrier on which a substantially rectangular base is arranged, which extends in a horizontal plane, for receiving a molded object to be produced by layer-by-layer material application. The printer is used for printing the molding object in a Cartesian coordinate matrix. For the molded object, geometric data assigned to the printing points located in a cartesian coordinate matrix are provided.

Above the base, a print head is arranged on the support, which print head has a nozzle device for discharging a material portion of the flowable material onto the base, which nozzle device is also referred to below as an emitter device. The emitter arrangement has a plurality of emitters configured as nozzles, which are arranged in a matrix in an oblique linear coordinate system in emitter rows offset parallel to one another and extending transversely to the emitter rows. Emitter rows adjacent to each other are respectively offset (shifted) from each other in the extending direction of the emitter rows, wherein the shift amount is smaller than the shift amount that each emitter in the emitter rows has. Each emitter column extends parallel to the two short edges (X-axis) of the rectangular base. The emitters are arranged such that each emitter of the emitter arrangement is located at a different X-position of the cartesian coordinate matrix in a direction extending parallel to the two short edges of the rectangular base. In this case, each X position of the coordinate matrix is associated with exactly one emitter of the emitter arrangement.

The emitter device can be moved in the Y direction parallel to the longitudinal extension of the base by means of a first positioning device arranged on the support and can be moved back and forth between two short edges that are remote from one another. Since the print dots lying directly adjacent to one another on a line extending in the direction of the X axis on two short edges parallel to the rectangular base are printed with nozzles arranged in different emitter columns of the emitter arrangement, the print head is positioned at different X positions when printing the print dots of the line adjacent to one another in such a way that the offset in the direction of the X axis of the different emitter columns is compensated. In this way, printing dots arranged directly next to one another in the X direction can be printed onto the base so closely offset from one another that they overlap locally. Nevertheless, the emitters of the emitter arrangement are spatially separated from one another and spaced apart from one another to such an extent that channels connecting the emitters with a storage device for the nozzle common material and/or conductor circuits can be arranged between the emitters.

The projectile of the projectile apparatus is movable relative to the base along with the storage means for the nozzle common material. Adjacent to the print head, a fixing device is arranged, which has an ultraviolet light source for crosslinking or curing the material layer applied by means of the emitter device. The fixture is movable with the printhead relative to the base.

Furthermore, the known 3D printer has a second positioning device, by means of which the base can be moved perpendicular to the plane in which the base extends towards the printing head and away from the printing head, i.e. can be positioned in height.

To manufacture the molded object, the print head is positioned above the base at a predetermined distance adjacent a first edge of the base. The data for the geometry of the first material layer are loaded from the data memory into a fast print buffer, in which the geometry data for the molded object to be produced are stored. The print head is then moved continuously by means of the first positioning device onto the opposite second edge of the base. At the same time, by actuating the individual emitters of the emitter arrangement accordingly, the material portions are each discharged onto the base at the locations on the base where the first material layer of the molded object is to be formed. The manipulation of the individual emitters is based on the current position of the print head and on the data located in the print buffer. The flowable material thus applied to the base is cured by irradiation with ultraviolet light, which is generated by means of the fixing device.

When the print head reaches the second edge of the bed, the horizontal feed movement of the print head is stopped and the geometrical data for another material layer to be applied on the previously produced material layer are loaded from the data memory into the print buffer. Furthermore, the base is lowered by means of the second positioning means by an amount corresponding to the thickness of the previously produced layer of material in order to apply a further layer of material on the layer of material. The print head is now continuously moved towards the first edge of the base by means of the first positioning means. At the same time, by appropriate actuation of the emitters, droplets of material are each delivered to the finished material layer at the location where a further material layer is to be formed. The flowable material thus applied to the base is in turn cured by irradiation with ultraviolet light, which is generated by means of the fixing device.

The disadvantage of this method is that it takes time for the printhead module together with the accessories to stop and accelerate at the edge of the base, which time cannot be used for printing. Said stopping and accelerating may account for up to 50% of the total printing time when the printing surface is small to medium and thus may significantly reduce the productivity of the process. Furthermore, heavy-duty print heads and the relatively large and heavy components associated therewith (e.g. storage devices in which there is a reserve of flowable material, wear-prone cable pulls and fixtures) must be stopped after each completion of one layer of material and accelerated in the opposite direction if further layers of material are to be applied. Due to the acceleration forces occurring in this case, the mechanical arrangement of the positioning device is subjected to loads, which lead to corresponding wear on the bearings and guides of the positioning device and thus adversely affect the accuracy of the printer.

Disclosure of Invention

It is therefore the object of providing a method of the type mentioned at the outset which makes it possible to produce at least one solid layer quickly in a simple manner by means of a projectile apparatus in which the projectile is arranged in an oblique linear coordinate system, on the basis of geometric data stored in a memory. Furthermore, the method should enable the application of a single radial line, consisting of a plurality of printing dots which are closely adjacent to each other and/or partially overlap, which should be printed according to the geometric data, onto the mount with an acceptable printing quality. Finally, the method should also be able to be implemented cost-effectively.

This object is achieved by the features of claim 1. This provides a method for producing at least one solid layer on a base which is rotatable about an axis of rotation according to predetermined geometric data,

a) in order to output the material portion of the nozzle common material onto the base, an emitter arrangement is provided, which has a number N of emitters configured as a material output nozzle, which emitters are arranged in a matrix form in emitter rows offset parallel to one another and extending transversely to the emitter rows, wherein the emitter rows adjacent to one another in the circumferential direction of the axis of rotation are offset from one another in each case in the direction of extension of the emitter rows such that the individual emitters of the emitter arrangement are arranged at different radial distances da (i) from the axis of rotation, wherein:

DA(i)＞DA(i+1)

wherein i belongs to [1. (N-1) ],

b) the geometric data is provided with printing points P_M...P_M+NThe printing dots are offset from one another in a matrix having a plurality of rows extending next to one another, in each of which a number Q of printing dots are arranged, such that:

PA(j)＞PA(j+1)，

wherein j belongs to [ M. (M + N-1) ] and M is more than or equal to 1 and less than or equal to Q-N,

wherein PA (j) is the j-th printing point P of the line concerned_jRadial distance to the axis of rotation and M is an integer,

c) for the printing point P where the material should be output onto the base_kFrom the associated printing point P of the emitter device_kEmitter D of_kWherein k is an integer between M and M + N-1,

d) the output of the material portions takes place in a plurality of printing cycles, in each of which a discharge device is triggered once in each case at a triggering point assigned to the printing cycle concerned for the output of the material, and the printing base and the discharge device are offset from one another by an angular distance relative to the axis of rotation in each case one printing cycle after the other,

e) all the printing points P to be printed in a row_M...P_M+N-1Is performed in a number of print cycles, the number of print cycles being greater than the number of emitter columns,

f) the printing cycle is selected for each print dot to be printed in such a way that, when the base is positioned at the triggering point relative to the emitter device, the angular difference between the rotational position of the triggering point of the printing cycle and the rotational position at which the print dot to be printed is arranged relative to the rotational axis is not greater in value than half the angular distance between the triggering points.

The above object is also achieved by the features of claim 2. This provides a method for producing at least one solid layer on a base which is rotatable about an axis of rotation according to predetermined geometric data,

a) providing a container in which at least one material layer of a liquid, pasty or powdery material is applied to a base, wherein, for irradiating the material with radiation from the solidified material, an emitter arrangement is provided, which has a number N of radiation emitters spaced apart from one another and directed toward the material layer, which are arranged in a matrix form in emitter rows offset parallel to one another and extending transversely to the emitter rows, wherein the emitter rows adjacent to one another in the circumferential direction of the axis of rotation are offset from one another in the direction of extension of the emitter rows in each case such that the individual emitters of the emitter arrangement are arranged at different radial distances da (i) from the axis of rotation, wherein:

DA(i)＞DA(i+1)

wherein i belongs to [1. (N-1) ],

b) the geometric data are assigned printing dots which are offset from one another in a matrix having a plurality of rows running next to one another in such a way that a number Q of printing dots are arranged in each of the rows, so that:

PA(j)＞PA(j+1)，

wherein j belongs to [ M. (M + N-1) ] and M is more than or equal to 1 and less than or equal to Q-N,

wherein PA (j) is the j-th printing point P of the line concerned_jRadial distance to the axis of rotation and M is an integer,

c) for printing spots P on which there should be a solid layer_kFrom the associated printing point P of the emitter device_kEmitter D of_kWherein k is an integer between M and M + N-1,

d) the irradiation of the material takes place in a plurality of printing cycles, in each of which the emitter device is triggered once for irradiation at a triggering point assigned to the respective printing cycle, and the base and the emitter device are offset from one another by an angular distance relative to the axis of rotation in each printing cycle,

e) all the printing points P to be printed in a row_M...P_M+N-1Is performed in a number of print cycles, the number of print cycles being greater than the number of emitter columns,

f) the printing cycle is selected for each print dot to be printed in such a way that, when the base is positioned at the triggering point relative to the emitter device, the angular difference between the rotational position of the triggering point of the printing cycle and the rotational position at which the print dot to be printed is arranged relative to the rotational axis is not greater in value than half the angular distance between the triggering points.

Thus, according to the invention, each print dot to be printed is assigned to one emitter and one print cycle. The arrangement of the emitters is carried out in such a way that one emitter is associated with each of the printing points, in which emitter the radial distance between the center of gravity of the area of the exit opening of the emitter and the axis of rotation of the emitter corresponds to the radial distance of the printing point from the axis of rotation, or, if no such emitter is present, an emitter is associated with the printing point, in which emitter the radial distance between the center of gravity of the area of the exit opening of the emitter and the axis of rotation of the emitter corresponds as good as possible to the radial distance of the printing point from the axis of rotation of the emitter.

The printing cycle and the allocation of the printing points are carried out in such a way that the rotational position of the trigger point, at which the material portion for the printing point is output by means of the projectile onto the base in the solution according to claim 1 or, in the solution according to claim 2, the liquid, pasty or powdery material located in the container is irradiated, coincides with the rotational position of the printing point to be printed, or, if no such trigger point is present, an activation point is allocated to the printing point whose rotational position coincides as good as possible with the rotational position of the printing point to be printed. By these measures it can be achieved that a single radial line to be printed is perceived as a single radial line to the human eye after printing. In particular, the perception of a single radial line as a V-shaped line or as a plurality of lines by the human eye is avoided.

Although the base and the nozzle arrangement are rotated relative to each other about an axis of rotation during printing, which corresponds to printing in a polar matrix, a print head which is actually provided for printing in a cartesian matrix is used as the nozzle arrangement. Such a print head with emitters arranged in an angular rectilinear matrix has the following advantages compared to a print head with emitters arranged in a polar matrix: the printhead is advantageously commercially available as a mass component cost. The method according to the invention can therefore be implemented cost-effectively and nevertheless achieves a high printing quality at least when printing lines arranged radially with respect to the axis of rotation.

"print dot" is understood to mean a location at which at least one material position is output onto a base in the solution according to claim 1 or at which a liquid, pasty or powdery material is irradiated in the solution according to claim 2, if appropriate in the presence of corresponding geometric data and if appropriate in the presence of further conditions. Thus, for example, in the solution according to claim 1, it may be expedient to provide a greater angular distance between the material output points adjacent to one another in the region of the base arranged close to the axis of rotation than in regions further away from the axis of rotation. The greater angular distance can also be achieved in such a way that not all printed dots are printed in the first-mentioned region. By these measures it is possible to apply, for example, materials with the same layer thickness in regions of the base that are remote and not at the same distance from the axis of rotation. A corresponding process is described for this purpose in WO2016/180842A 1.

The geometry data is preferably stored as a bitmap and in the solution according to claim 1 may have one material output value for each printed dot. In the simplest case, the material output value can have two states, for example a logical value "1" when at least one material portion is to be applied to the base at a print point and a logical value "0" when no material is to be applied at a print point. The material output value may also comprise more than two states when different amounts of material should be output onto the base for each printed dot. The geometry data may also have coordinates for the location of the printed dots, if desired. It is also conceivable to provide coordinates only for those print points on which material should be applied to the base. In which case the material output value can be eliminated.

In one embodiment of the invention, the matrix is a cartesian matrix and the rows in which the printing dots are offset from one another run parallel to one another. In this embodiment of the method, the individual radial lines to be printed are printed such that they are perceived by the human eye as individual radial lines from a greater distance after printing. In the case of straight lines which do not extend radially, distortions in the form of bends can occur. Thus, for example, a straight line arranged perpendicularly to a line oriented radially with respect to the axis of rotation and extending parallel to the base is printed as a circular line concentric with the axis of rotation.

In a preferred embodiment of the invention, the matrix is a polar matrix and the rows in which the printing dots are offset from one another are arranged radially with respect to the axis of rotation, and preferably the rows adjacent to one another are offset from one another by the angular distance of the triggering point. It is even possible here for the printing dots to be arranged first in a cartesian matrix and then converted into a polar matrix. This achieves good conformity between the position of the printing point to be printed, which is set according to the geometric data, and the location on which the material portion for the printing point is applied to the base by means of the nozzle. That is, the solid layer can be printed with low distortion.

Expediently, for a number of directly successive trigger points equal to the number of printing cycles, for each printing point P, the trigger point concerned is in each case assigned to_M...P_M+N-1The emitter means being designed for the printing of dotsPrinting, as the printing point P concerned_M...P_M+N-1One printing cycle is set, and then each printing point P to be printed is set for each line separately according to the set_M...P_M+N-1The emitter device is designed for the printing of the print dot, a print cycle is assigned, and the emitter device is triggered when the trigger point assigned to the print cycle concerned is reached. Thus, the assignment of print dots to print cycles need only be determined for a number of print dot rows equal to the number of print cycles and can then be used for all other rows having print dots. The print cycle and the arrangement of the print points can be realized by means of hardware circuits. However, it is also conceivable to implement the configuration by means of an operating program running on a microcomputer or similar control device.

In a further development of the invention it is provided that,

a) providing a data memory, storing geometry data in the data memory,

b) providing a ring memory having a number of storage spaces which is at least equal to the number of printing cycles, each storage space comprising a number of storage positions which is equal to the number (N) of emitters of the emitter arrangement, each of the storage positions being associated with one emitter,

c) for a number of directly successive printing cycles equal to the number of printing cycles, one of the storage spaces is respectively assigned to each of the printing cycles,

d) for a first row of printed dots stored in the data memory, a number of printed dots equal to the number of emitters of the emitter arrangement is read from the data memory, the emitter arrangement being designed for the printing of these printed dots,

e) for the emitters assigned to the first row of printing points, an activation value is stored in each storage position of the annular memory assigned to the emitter, which activation value specifies whether the emitter assigned to the printing point concerned should be activated in a printing cycle assigned to the storage space concerned,

f) for another row of geometric data, a number of printed dots equal to the number (N) of emitters of the emitter arrangement designed for printing of these printed dots is read from the data storage,

g) for the emitters assigned to the other row of printing points, an activation value is stored in each storage position of the annular memory assigned to the emitter, which activation value specifies whether the emitter assigned to the printing point concerned should be activated in a printing cycle assigned to the storage space concerned,

h) repeating steps f) and g) until a number of print dots equal to the number of emitters (N) has been respectively read from the data memory for a number of rows equal to the number of print cycles and activation values corresponding to these print dots have been stored in the ring memory,

i) positioning the base and the emitter arrangement relative to one another at trigger points (A to H) associated with a printing cycle in which an activation value is initially stored in a storage space and the emitter of the emitter arrangement is actuated as a function of the activation value stored in the storage space,

j) if at least one further print dot is to be printed,

the storage spaces are exchanged periodically in such a way that the storage space provided with the triggering points (A to H) at which the base and the emitter arrangement are finally positioned relative to one another for triggering the emitters is the first storage space, and then

-repeating steps f) to j).

The method can thus be implemented in a simple manner with a saving in memory space. The projectile arrangement is expediently assigned a print buffer, in which a memory location is provided for each projectile of the projectile arrangement, an activation signal is stored for each projectile in each print cycle in the memory location of the print buffer assigned to the projectile concerned as a function of the geometric data, and the projectile arrangement is subsequently triggered in the print cycle in such a way that the respective projectile is actuated as a function of the activation signal stored in the memory location assigned to the projectile. This ensures that all the projectiles to be actuated are actuated simultaneously when a trigger occurs.

In a preferred embodiment of the invention, for printing a print ring which is arranged concentrically to the axis of rotation and is defined by an inner circular track and an outer circular track, respectively, at least one first and one second emitter device are provided, wherein the respective emitter devices are positioned relative to the axis of rotation such that the arithmetic mean of the inner circular track and the outer circular track of the first emitter device differs from the arithmetic mean of the inner circular track and the outer circular track of the second emitter device, and the first emitter devices are assigned a number M which differs from the number M of the second emitter devices. Thus, the bed may also be printed simultaneously with two or more emitter devices arranged at different distances from the axis of rotation. The individual emitter devices are in this case preferably each designed as a module or as a print head. In this case, each print head can even be assigned its own print buffer. Since the rows and columns of the individual emitter arrangements each run parallel to one another, the emitter arrangements or print heads assigned to different print rings can be constructed identically, in contrast to polar printing arrangements in which the emitters are offset from one another on radial lines arranged radially with respect to the axis of rotation. This enables a simple and cost-effective implementation of the method. With the method described, a base having almost any large surface can be printed when there are a corresponding number of print heads. Preferably, the printing rings arranged adjacent to one another abut against one another or slightly overlap one another in such a way that a gap-free printing of the base in the radial direction is possible.

Advantageously, the emitter columns of the emitter arrangement are arranged symmetrically with respect to a radial plane, which is formed by the axis of rotation and the normal to the axis of rotation, such that the emitter columns extend parallel to the radial plane. When the emitter arrangement has an odd number of emitter columns, the emitter columns are preferably arranged such that the central emitter column or a linear extension thereof extends through the axis of rotation. When the print head arrangement has an even number of emitter rows, the axis of rotation is preferably arranged in the middle between the two innermost emitter rows or their linear extensions.

In a further advantageous embodiment of the invention, at least two emitter arrangements are provided, which are offset from one another by a rotation angle relative to the rotation axis, wherein the emitters of the individual emitter arrangements are each controlled for applying the material portions according to at least one of claims 1 to 9. Thereby enabling printing of the chassis. In the solution according to claim 1, different materials can be applied to the base with the respective emitter arrangement. The respective emitter arrangements are preferably arranged at the same distance from the axis of rotation. However, it is also possible to apply the same material to the base by means of emitter devices which are offset from one another by a rotation angle relative to the axis of rotation. The radial distance between the projectile device and the axis of rotation can be selected such that the base can be coated with material in the radial direction without interruption.

Preferably, the emitters adjacent to one another within an emitter column are offset from one another by a constant first grid distance, wherein the emitter columns adjacent to one another are offset from one another by a constant second grid distance, and the first grid distance deviates by less than 20%, in particular by less than 10%, and in particular coincides with the product of the number of emitter columns and the second grid distance. This can further reduce distortion at the time of printing.

Three-dimensional shaped objects can be manufactured with the method according to the invention. For this purpose, in the method for applying a material by means of a nozzle, a plurality of material layers of a nozzle-generic material are applied one above the other, wherein the distance between the nozzle device and the base is increased in each case in layers by the thickness of the material layer applied most recently, and each material layer is cured separately after its application, and then a further material layer is applied to this material layer. If the material is a crosslinkable polymer material, curing of the material can be effected, for example, by irradiation with UV light of a suitable wavelength. In a method according to claim 2, for producing three-dimensional shaped objects, a plurality of material layers of liquid, pasty or powdery material are cured in a superimposed manner over the entire surface and/or in regions by irradiation with an emitter device. The method enables rapid and uninterrupted application of multiple material layers.

Drawings

Embodiments of the invention are explained in detail below with the aid of the figures. In the drawings:

fig. 1 shows an apparatus for producing a three-dimensional solid molded object layer by applying a nozzle-generic material, wherein the apparatus has a base which can be rotated about an axis of rotation, to which a number of material layers for the molded object are applied,

figure 2 shows a view similar to figure 1 after further layers of material have been applied and the susceptor has been lowered relative to figure 1,

FIG. 3 shows a schematic top view of an emitter arrangement configured as a print head, comprising a plurality of emitters configured as nozzles arranged in rows and columns in a matrix, wherein the position of the individual exit openings of the emitters is indicated by a circle, and the rows/columns in which the exit openings are arranged are marked by straight lines running parallel to one another,

FIG. 4 shows a graphical representation of printed dots defining layers of a polar matrix of a model of a three-dimensional shaped object, wherein the printed dots are located in rows A to I arranged radially with respect to an axis of rotation and a plurality of printed dots are arranged in each row respectively,

fig. 5A to 5I show views similar to fig. 3, which show the emitter device positioned above the base to be printed when printing the print dot shown in fig. 4, wherein the base is positioned in fig. 5A to 5I in a rotating manner at different triggering positions relative to the emitter device, and the rows of the matrix are denoted by the letters a to I according to fig. 4,

fig. 6A to 6H show schematic representations of the memory contents assigned to the individual trigger points of a ring memory in which the activation values for the individual emitters of an emitter arrangement are stored, wherein the letters a to I represent the rows of a matrix on which the print points to be printed with the emitter concerned lie, wherein the letters a to I highlighted in bold indicate that the emitter concerned should be activated at the trigger point concerned, and the letter E, O not printed in bold indicates that the emitter concerned should not be activated at the trigger point,

fig. 7B to 7I show the contents of the ring memory after the periodic exchange of the memory contents of the ring memory shown in fig. 6A to 6H and the overwriting of the memory contents of the ring memory according to fig. 6A, the ring memory contents having activation values for further trigger points,

fig. 8A to 8H show views similar to fig. 5A to 5H, but in which full black circles mark locations at which partial regions of the molded object are generated upon triggering of the emitter device in the current printing cycle or the previous printing cycle shown in the figures, depending on the storage content of the ring memory, while circular lines mark locations at which partial regions of the molded object are not generated,

fig. 9 shows a flow chart illustrating the steps that are experienced when processing the geometric data for shaping the object and when manipulating the emitter device,

fig. 10 shows the lines denoted by "a" in fig. 4, which are printed with the device shown in fig. 1 and 2, wherein the partial regions of the molded object that are produced on the base to be printed are shown by full black circles and the locations at which the partial regions of the molded object are to be applied to the base according to the geometric data for printing the lines "a" are marked by circular lines,

figure 11 shows a graphical representation of geometric data in the form of a cartesian matrix,

figure 12 shows the printing result when printing the geometry data of figure 11 using the method according to the invention,

fig. 13 shows the printing result when printing the geometry data of fig. 11 using a method not according to the invention, wherein the number of printing cycles is equal to the number of nozzle columns,

fig. 14 and 15 show a partial top view of a base of a device for the layer-by-layer production of three-dimensional shaped objects, wherein the base has a plurality of emitter arrangements assigned to different print rings,

fig. 16 shows an apparatus for producing a three-dimensional shaped object from a stereolithography template, wherein the apparatus has a container in which a rotatable base and a material that can be cured by irradiation with electromagnetic radiation are arranged,

FIG. 17 shows a longitudinal section through the axis of rotation of the apparatus shown in FIG. 16, an

Fig. 18 shows a view similar to fig. 17 after curing of further layers of material and lowering of the mount relative to fig. 17.

Detailed Description

In a method for the layer-by-layer production of solid molded objects on a base 1 which can be rotated about a rotational axis 2 according to predetermined geometric data, a circular-ring-shaped rotating disk having a base 1 is provided, which is mounted on a stationary carrier 3 so as to be rotatable about a vertical rotational axis 2 (fig. 1 and 2). The support 3 has a support surface on its underside, by means of which the support can be placed, for example, on a table or on the floor of a room.

The base 1 is in driving connection with a first positioning device having a first drive motor 4, by means of which the drive base 1 can be rotated in the direction of the arrow 5 and the base can be positioned as a function of a rotational position setpoint signal provided by an operating device 6. For this purpose, the first drive motor 5 is connected to a first position controller integrated into the control device 6, which has an encoder 7 for detecting a rotational position signal of the base 1. By means of the first positioning device, the base 1 can be rotated continuously and without stopping about the axis of rotation 2 relative to the stand 3 through almost any angle greater than 360 °.

Furthermore, the base 1 is in driving connection with a second positioning device having a second drive motor 8, by means of which the base 3 can be moved up and down in the direction of the double arrow 9 relative to the stand 3 and can be positioned as a function of a height position setpoint signal provided by the operating device 6 (fig. 1 and 2). The positioning may be performed stepwise or continuously. For this purpose, the second drive motor 10 is connected to a second position controller integrated into the control device 6, which has a position sensor 10 for detecting the height position of the base 1.

In order to carry out the method, an emitter device 11 is also provided, which is designed as a print head with 30 emitters 12 provided with controllable valves or pumps, which are designed as material outlet nozzles from which material portions (for example droplets) of a hardenable material can be respectively output, which are common to the nozzles. Instead of a print head, another emitter matrix with fixed emitters may be used. The material may be, for example, a photo-crosslinkable polymer, which is stored in a storage device, not shown in any more detail, which is connected to the emitter 12 via a line.

The exit openings of the emitters 12 are arranged above the base 3 in a plane spaced apart from the plane extending parallel to the plane of the base 1 and are positioned in a matrix with a plurality of emitter columns 13 arranged parallel to one another and emitter rows 14 offset parallel to one another and extending transversely to the emitter columns 13. A plurality of emitters 12 are arranged in each emitter column 13 and each emitter row 14, respectively.

In the emitter row 13, the center of gravity of the faces of the exit openings of the individual emitters 12 are offset from one another by a constant distance X along lines spaced parallel to one another (fig. 3). The emitter rows 13 adjacent to each other in the circumferential direction of the rotational axis 2 are respectively offset from each other by an offset V in the extending direction of the emitter rows 13. The offset V is selected such that the individual emitters 12 of the emitter arrangement 11 are arranged at different radial distances da (i) from the axis of rotation 2. For the radial distance, the following applies:

DA(i)＞DA(i+1)，i∈[1..29]

the first emitter 12 is thus at a maximum distance from the axis of rotation 2 and the thirtieth emitter 12 is at a minimum distance from the axis of rotation 2.

The emitter arrangement 11 is connected to a print buffer 15, in which an activation value can be buffered for each emitter 12 of the emitter arrangement 11. The activation value may have, for example, a logical value of "1" or a logical value of "0".

Furthermore, the emitter arrangement 11 has a trigger input, at which a trigger signal can be applied. In each trigger received at the trigger input, all emitters 12 of the emitter arrangement 11 for which an activation value "1" is stored in the print buffer 15 in each case output a material portion. Emitters 12 for which an activation value of "0" is stored in the print buffer, i.e. emitters 12 which do not output a material portion, are not actuated upon receipt of a trigger.

In order to cure or crosslink the material layer located on the base 1 and/or the layer stack located on the base 1 and having a plurality of material layers applied by means of the emitter device 11, a UV light source 16 is provided, which is positioned on the base 1 such that it faces the base 1 with its emission side.

By means of the device having the base 1, the emitter arrangement 2, the control arrangement 6 and the UV light source 16, a plurality of layers of nozzle-generic material can be applied to the base 3 by layer-by-layer application and curing in order to produce the three-dimensional solid shaped object 17A, 17B, 17C, 17D.

The control device 6 is connected to a higher-level computer 18, for example a personal computer, which has a data memory 19 in which the geometric data are stored for the individual material layers. The geometric data are assigned printing dots which are arranged in a pole matrix having a plurality of rows 20 extending next to one another, the linear extension of each row intersecting the axis of rotation 2. The rows 20 adjacent to one another in the circumferential direction of the axis of rotation 2 are offset from one another by an angular distance W, respectively. In each row 20, in each case 30 print dots are arranged, which are offset from one another in such a way that for the jth print dot P_jThe radial distance pa (j) applies:

PA (j) > PA (j +1), where j ∈ [1..29]

First printing point P₁And therefore the maximum distance from the axis of rotation 2, and the thirtieth printing point P₃₀At a minimum distance from the axis of rotation 2.

The geometric data can be provided, for example, by means of CAD software which can be run on the computer 18. Furthermore, software can be executed on the computer 18, which generates the geometric data for the individual layers of the molded object 2A, 2B, 2C, 2D from the geometric data for the molded object. To load the geometry data into the print buffer 14, the computer 18 is connected to the control device 6.

Each print point P stored in the geometry data_k(for the printing point, the material is to be discharged onto the base 1) in each case one emitter 12 of an emitter arrangement 11 is assigned to which the printing point P is to be set_kIs applied to the base 1 or to a layer of cured material located on the base. The assignment is carried out according to the numbers given above for emitters 12 and printed dots in such a way that the number of emitters 12 is associated with printed dot P, respectively_kThe numbering of (a) is consistent. Printing point P_kPrinting takes place accordingly with a radiation emitter 12 whose distance from the axis of rotation 2 is as good as possible from the print point P_kThe distances to the axis of rotation 2 are uniform.

The output of the material portions takes place in a plurality of printing cycles, in each of which the emitter device 11 is triggered once in each case at a triggering point a.. H assigned to the printing cycle concerned, at which the base 1 is in each case positioned in a predetermined rotational position relative to the emitter device 11, in order to output the material. At each triggering, all emitters 12 of the emitter arrangement 11 output a material portion for which an activation value "1" is stored in a print buffer 15 in each case. The base 1 and the emitter arrangement 11 are each offset from one another by an angular distance W, which is provided in the circumferential direction of the axis of rotation 2 by adjacent rows 20 of printing dots according to geometric data. As can be seen in fig. 5A to 5I, all the print dots P to be printed of one line are printed in eight print cycles, respectively₁...P₃₀. Therefore, the number of printing cycles is larger than the number of emitter columns 13 of the emitter arrangement 11.

Each print point P to be printed, in addition to emitter 12_k(where k ∈ [1..30 ]]) And is also assigned to each of the eight printing cycles. This arrangement is realized in such a way that when the base 1 is in relation to the launchWhen the body device 11 is positioned at the trigger position a.. H, the rotational position of the trigger position a.. H and the print point P to be printed of the print cycle_k(where k ∈ [1..30 ]]) The angular difference between the rotational positions arranged relative to the rotational axis 2 is not numerically greater than half the angular distance W between the triggering points a.. H. For printing point P_k(where k ∈ [1..30 ]]) Arranged exactly midway between the two trigger positions, the printing point P concerned_kIs assigned to one of the two triggering points.

From fig. 5A to 5I, the printing points P for the respective trigger sites a_kAnd emitter 12. The emitters 12 which output material at the triggering points a.. H concerned are marked by circles filled with black. In fig. 5A to 5I, emitters 12 which do not emit material at the trigger points a.

The letters in these circles indicate which of the rows of printed dots a.. I shown in fig. 4 the printed dots assigned to the emitter 12 concerned belong to. The numbers in the circles illustrate in which print cycle emitter 12 should output for printing a dot P_kThe material of (1). The circular lines, which neither enclose a number nor a letter, mark emitters 12 which, from the beginning of the printing process, have not been provided with any printed dot P_k。

Fig. 8A to 8H illustrate the state of material application at each trigger site a. The drawings of the printed dots on which material has been applied to the base 1 correspond to the drawings of the emitter 12 in figures 5A to 5I. The material is applied to the chassis 1 at the first activation site (fig. 8A) only at the site designated "a 1". In fig. 8B, material is additionally applied to the chassis 1 at locations indicated by "a 2" and "B1". In fig. 8C, material is applied to the base 1 at ten further locations denoted by "a 3", "B2", and "C1", and so on.

For printing point P_kWith the arrangement of the triggering points a. In these storage spacesEach of the storage spaces is respectively assigned to one of the eight printing cycles. Each storage space comprises 30 storage locations, respectively, i.e. one storage location for each emitter 12 of the emitter arrangement 11.

Next, how data is processed in the ring memory during the printing process is explained. First, 30 print points P are read from the data store for the first row 20 of geometric data_k(where k ∈ [1..30 ]]). These printing points P_kEach associated with one of the thirty emitters 12, as described above. In the storage positions of the ring memory assigned to these emitters 12, an activation value is stored with a logic value "1" or "0", respectively. In this case, a value of "1" indicates that the printing point P assigned to the memory space concerned should be manipulated or activated in a printing cycle assigned to the memory space concerned_kEmitter 12.

In a further method step, 30 print points P are read from the data memory for another row 20 of print points stored in the data memory_k(where k ∈ [1..30 ]]). These printing points P_kEach print dot in (a) is assigned to one of the thirty emitters 12, as described above. In each case one activation value is stored in the storage positions of the annular memory assigned to the emitters 12, which activation value indicates whether the printing point P assigned to the relevant printing point P should be manipulated in the printing cycle assigned to the storage space concerned_kEmitter 12.

The steps mentioned in the last two paragraphs are repeated until 30 print points P have been read from the data store for all eight print cycles, respectively_k(where k ∈ [1..30 ]]) And the activation values corresponding to these printed dots have been stored in the ring memory (fig. 6A to 6H).

In a further method step, the base 1 and the emitter arrangement are positioned relative to one another at a trigger point a.. H assigned to a printing cycle in the storage space of which the activation values are initially stored, and the emitter 12 of the emitter arrangement 11 is actuated as a function of the activation values stored in the storage space. Each emitter 12 is operated here, for which an activation value "1" is stored in a ring memory for the trigger point a.. H concerned. At the triggering points a.. H, the emitters 12 for which no material output value "1" is stored in the ring memory for the triggering point a.. H concerned are not actuated.

It is now checked whether all rows of material layers to be printed have been printed. If this is not the case, the storage spaces are exchanged periodically in such a way that the storage space provided with the triggering location a at which the base 1 and the emitter arrangement 11 were positioned relative to one another the most recent time is the first storage space (fig. 7B to 7I). For the other row, the geometric data are then read in from the data memory 19 and processed in a corresponding manner.

After all the rows of printed dots of the current layer of material have been printed, it is checked whether at least one further layer of material should be printed. If this is the case, the base 1 is lowered in thickness with respect to the emitter arrangement 11 by a layer of material, in order thereafter to print another layer of material as described above.

The row of geometric data "a" printed on the base 1 according to the method of fig. 4 is shown in fig. 10. The material portion output onto the base 1 is marked by a full black circle. These circles are also visible on the right side of fig. 8H, where they are (from top to bottom) denoted A3, A3, a4, a5, a6, a7, a2, A3, a4.. a5, a6, A8. The remaining circles depicted in fig. 8H, which are assigned to the rows of geometric data "B" to "I" in fig. 4, are not shown in fig. 10 for reasons of clarity.

In fig. 10, the locations (nominal print data) at which print dots according to the geometric data for printing row "a" in fig. 4 are to be applied to the base are surrounded by circular lines. As can be seen, good consistency of the printing results with the geometry data is achieved in the middle part of the line. At each end of the line, a large deviation between the printed result and the geometric data, respectively, occurs. This occurs primarily because the distances between the individual emitters 12 of the emitter arrangement 11 and the arrangement of the emitters 12 are selected differently than is usual in practice for reasons of better readability of the drawing. For the method according to the invention, it is preferred to have an emitter arrangement 11 of larger dimensions in the radial direction than in fig. 3. Thus, for example, the emitter arrangement 11 may have 1024 emitters in each column instead of the five emitters 12 shown in fig. 3. Furthermore, it is preferred for the method according to the invention that the emitter device 11 has a dimension perpendicular to its longitudinal axis and parallel to the plane of the base 1 with a quotient to the inner diameter of the printable area of the base 1 which is smaller than that shown in fig. 5A to 5I.

As can be seen in fig. 4, for reasons of better readability of the drawing, the rows with the printed dots are furthermore arranged such that they are spaced apart from one another by gaps. However, it is preferred for the method according to the invention for the printing dots of the rows adjacent to one another to overlap locally in the matrix.

In fig. 11, geometric data for printing a cartesian line pattern having a plurality of intersecting lines extending perpendicular to each other is graphically illustrated for one embodiment. In fig. 12 it can be seen how the lines printed with the method according to the invention are arranged on a base 1. Distortions occur due to different coordinate systems (cartesian geometry data and polar printing equipment). The horizontal lines of geometric data are printed as circular lines, and the vertical lines of geometric data extend radially with respect to the rotational axis after printing. Despite these distortions, a single printed line is still perceived as a single line to the human eye.

FIG. 13 shows a print result of printing the geometric data in FIG. 11 using a method not in accordance with the present invention in which the number of print cycles is equal to the number of emitter columns. It can clearly be seen that the vertical lines in fig. 11 appear as two lines of a V-shaped arrangement, respectively, to the human eye after printing. Such an error occurs because the different circumferences of the region to be printed of the base 1 at its inner and outer edges are not compensated in fig. 13. Thus, the projectile 12 cannot be properly triggered, particularly at the inner edge of the base.

In the embodiment shown in fig. 14, in order to print a print ring which is arranged concentrically with the axis of rotation 2 and is defined by an inner circular track and an outer circular track, respectively, a plurality of emitter devices 11A, 11B, 11C, 11D are provided. The respective emitter arrangements 11A, 11B, 11C, 11D are positioned relative to the axis of rotation 2 such that the arithmetic mean of the inner circular trajectories and the outer circular trajectories of the respective emitter arrangements 11A, 11B, 11C, 11D differ from each other. Each of the emitter arrangements 11A, 11B, 11C, 11D has 27 emitters 12. Emitter device 11A is used to print printed dots 1.. 27, emitter device 11B is used to print printed dots 28.. 54, emitter device 11C is used to print printed dots 55.. 81, and emitter device 11C is used to print printed dots 82.. 108. The emitter arrangements 11A and 11C are arranged in a first rotational position relative to the axis of rotation 2 and are triggered at the same triggering point. The emitter columns 13 of the emitter devices 11A are aligned in a straight line with the corresponding emitter columns 13 of the emitter devices 11C. The emitter arrangements 11A and 11C are thus associated with each other, which is schematically illustrated in fig. 14 by the dot-connected lines.

The emitter arrangements 11B and 11D are arranged in a second rotational position, different from the first rotational position, with respect to the rotational axis 2. Thus, the emitter devices 11B and 11D are also associated with each other.

This arrangement with separately placed print heads or emitter arrangements 11A to 11D is obtained when using emitter arrangements 11A to 11D which have a small printing width in the radial direction. The emitter devices 11A, 11B, 11C and 11D will be placed in a row when using a print head whose printing width extends in the radial direction over the entire turret width of the base 1.

As can be seen in fig. 15, a plurality of emitter arrangements 11A, 11C and 11A ', 11C' or 11B, 11D and 11B ', 11D' associated with one another can be arranged offset from one another in the circumferential direction of the axis of rotation 2.

In the exemplary embodiment of the invention shown in fig. 16 to 18, a device is provided, which has a container 22 in which a liquid, pasty or powdery material 23 is applied to the base 1. In order to irradiate the material 23 with high-energy electromagnetic radiation 21, one of the emitter arrangements 11, 11A, 11B, 11C, 11D has a plurality of radiation emitters 12 spaced apart from one another, which are each in the form of a light-emitting diode. In order to focus or focus the radiation 21 output by the individual emitters 12, in each case one optical component, which is not illustrated in any more detail in the figures, is arranged in the radiation path of the emitters 12.

The wavelength and power of the electromagnetic radiation 21 generated by the emitter 12 can be adjusted to the flowable material 23 in such a way that it can be solidified at the irradiation site by irradiation with the electromagnetic radiation 21. In a flowing or flowable material 23, "curing" is understood to mean hardening the material 23 into a solid material, in particular by crosslinking of the polymers and/or copolymers contained in the material 23. In the case of the powdery material 23, "solidification" is understood to mean that the material particles present as solid particles are heated by irradiation with the electromagnetic radiation 21 and subsequently cooled such that they are firmly connected to one another.

The emitter devices 11, 11A, 11B, 11C, 11D have a plurality of emitter rows 13A, 13B, 13C, and the center points of the emitters 12 in the emitter rows are offset from each other on a straight line. The arrangement of the radiation emitters 12 corresponds to the arrangement of the emitters 12 configured as nozzles in fig. 3, 5A to 5I, 8A to 8H, 14 and 15, so that the description of the emitter arrangements 11, 11A, 11B, 11C, 11D depicted in these figures correspondingly applies to the embodiments according to fig. 17 to 18, with the difference, however, that the emitters 12 in the embodiments according to fig. 16 to 18 output radiation 21 instead of material, and that the radiation 21 is directed at the flowable material 23.

The base 1 located in the container 22 is positioned rotationally about the axis of rotation 2 relative to the emitter arrangement 11, 11A, 11B, 11C, 11D and the radiation generated by means of the emitter 12 is directed to the layer of material located on the surface of the material 23 so that the material 23 is cured at least one irradiation site.

The emitter arrangement 11 is connected to a print buffer 15, in which an activation signal can be buffered for each emitter of the emitter arrangement 11. For actuating the radiation emitter 12, an actuating device is provided, which has a trigger input. In each trigger received at the trigger input, all emitters 12 of the emitter arrangement 11 for which a value "1" is stored in the print buffer 15 in each case output radiation 21 in the direction of the material 23. Emitters 12 for which a value of "0" is stored in the printer buffer, i.e. emitters 12 which do not output radiation 21, are not actuated upon receipt of a trigger. Fig. 6A to 6H and 7B to 7I, which show the activation signal values at the various trigger sites of the device shown in fig. 1 and 2 for the emitter arrangement 11, apply correspondingly to the embodiments in fig. 16 to 18.

In the exemplary embodiment shown in fig. 16 to 18, the base 1 is in driving connection with a first positioning device having a first drive motor 4, by means of which the base 1 can be driven in rotation in the direction of the arrow 5 and can be positioned as a function of a rotational position setpoint signal provided by the actuating device 6. For this purpose, the first drive motor 5 is connected to a first position controller integrated into the control device 6, which has an encoder 7 for detecting a rotational position signal of the base 1. By means of the first positioning device, the base 1 can be rotated continuously and without stopping about the axis of rotation 2 relative to the support 3 through almost any angle greater than 360 °.

Furthermore, the base 1 is in driving connection with a second positioning device having a second drive motor 8, by means of which the base 3 can be moved up and down in the direction of the double arrow 9 relative to the support 3 and can be positioned as a function of a height position setpoint signal provided by the actuating device 6 (fig. 18). The positioning may be performed stepwise or continuously. For this purpose, the second drive motor 10 is connected to a second position controller integrated into the control device 6, which has a position sensor 10 for detecting the height position of the base 1.